Cathodion dies, triggering itself and its undying ability.
Resolve the first Cathodion trigger, adding ({C} magic symbol) ({C} magic symbol) ({C} magic symbol) .
Resolve the second Cathodion trigger, returning it to the battlefield with a +1/+1 counter and a vigilance counter.
Resolve the Carrion Feeder ability, putting a +1/+1 counter on it.
Activate Tayam by paying ({3} magic symbol) , removing a counter from Carrion Feeder and removing both counters from Cathodion, causing you to mill three cards and allowing you to return a permanent card with mana value three or less from your graveyard to the battlefield.
Repeat.
Results
Infinite death triggers.
Infinite ETB.
Infinite LTB.
Infinite sacrifice triggers.
Infinite self-mill.
Put all permanents with mana value three or less from your library and graveyard onto the battlefield.